Hagrid is probably the single most important person in Harry's development. He gave him self-worth, showed him that someone who makes serious mistakes can still be a good person, and taught him loyalty beyond anything Harry would ever see.
The Moral Of Harry Potter --> Open to see all. The only one I disagree with is Lupin. It should read "Prejudice about something that is misunderstood will lead you nowhere, but kindness and compassion to everyone will create love."